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BRUSHED POL LY BUILDS A BASE Three or four coats of liquid polyurethane, sanded smooth between coats, are enough to give the wood real protection without a thick, plastic lo ook. A light touch. Lay on a coat of polyurethane starting a few inches from one edge and brushing off the opposite edge. Use a light touch, holding the brush at about 45º to the surface. After the first pass, land the brush just inside the far end and return, smoothing the strip of wet finish until you cover the small dry area and go lightly off the end. By brushing off the ends and not onto them, you avoid having finish run down the edges. surface, we’re still dealing with an eyecatching large, flat surface, so good preparation is essential. To learn how to flatten and smooth a tabletop using handplanes and a scraper, see Bob Van Dyke’s Fundamentals: “Creating an attractive tabletop” in FWW #210. If you are more comfortable with a randomorbit sander, start at P100 grit and work your way up to P220 grit, then hand-sand with the grain using the final grit. Remove the dust using a vacuum or compressed air to clean out the pores. The next step is to apply a thin coat of shellac to the whole piece. As well as greatly reducing the likelihood of blotching, the shellac gives the wood a slightly warmer tone and lets you build a sheen faster with the gel finish. You may have heard that polyurethane will not adhere 42 FINE WOODWORKING to shellac. This is true if you use shellac containing wax, such as Zinsser’s clear or amber Bulls Eye Shellac. Polyurethane will adhere perfectly to dewaxed shellac such as Zinsser’s SealCoat or your own mixture using dewaxed shellac flakes. Mix a 1-lb. to 11⁄2-lb. cut (dilute the Seal- Coat by about a third with denatured alcohol). You can apply the shellac with a natural or synthetic filament brush, but I find it just as quick (and easier on vertical surfaces) to wipe on the shellac with a cotton cloth. It also requires less sanding afterward. Let the shellac dry for two to four hours depending on the temperature and the humidity, and then lightly sand the surface with P320-grit paper wrapped around a cork or cork-faced block. All you are doing is removing any particles, dust nibs, etc. to leave a smooth surface. Wipe and vacuum away the dust. Brush polyurethane to add toughness Because you won’t be brushing on the final coats, you don’t need a really expensive brush that leaves a perfect surface. A $10 to $20 natural-bristle brush, 2 in. or 21⁄2 in. wide, works fine for most surfaces. If you have no experience brushing finishes, or if your attempts have been below par, this is a painless way to build your brushing skills and confidence. You can use any brand of oil-based gloss polyurethane, even those recommended for floors, but the viscosity between different brands varies greatly. The Minwax Fast-Drying Polyurethane I used is about the consistency of 1% or 2% milk and can be used straight from the can. If your finish Photos, facing page (top three): Matthew Kenney